AB1382 IMPACT OF CENTRAL SENSITIZATION ON PAIN IN PATIENTS WITH CHRONIC INFLAMMATORY RHEUMATIC DISEASES
Authors: I. Berrichi, F. Z. Taik, H. Fouzia, N. Soba, M. Fourtassi, F. E. Abourazzak
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> Pain in chronic inflammatory rheumatism (CIR) is polymorphic; nociceptive, neuropathic and central sensitization (CS) may be involved. The International Association for the Study of Pain (IASP) defines central sensitisation as <b>«</b> Increased responsiveness of nociceptive neurones in the central nervous system to their normal or sub-threshold afferent input » (1) Chronic inflammation can play an important role in this CNS hyperexcitability. During CIR pain may persist, despite objective control of inflammation suggesting the involvement of SC phenomena. <h3>Objectives</h3> The objective of this study is to detect the impact of central hypersensitivity phenomena on pain in patients suffering from CIR. A second objectif is to look for other factors associated with this central sensitization. <h3>Methods</h3> This is a cross-sectional study that included all patients aged ≥ 18 years followed up for chronic inflammatory arthritis (SPA, RA, undifferentiated CIR) presenting to the rheumatology department.Patients with psychiatric or memory disorders or who refused to participate in the study were excluded. Sociodemographic data, comorbidities and treatments received were collected.Nociceptive pain was assessed by visual analogue scale (VAS),disease activity by DAS-28 and ASDAS and central sensitization by the validated Moroccan version of the Central Sensitization Inventory part A (CSI-A). This inventory has 2 parts: Part A measures a range of 25 somatic and emotional symptoms associated with central sensitization, scored from 0 (never) to 4 (always), for a possible total score of 100. Part B concerns the recording of previous diagnoses related to central sensitization (not used in our study). A CSI-A score ≥ 40 was the threshold considered for the definition of CS. The Pain catastrophizing scale (PCS) was used to assess pain-related catastrophic thoughts and the PHQ-9 (Pain Health Questionnaire) to assess the severity of depressive symptoms. <h3>Results</h3> We included a total of 189 patients, 107 (56.61%) had rheumatoid arthritis, 67 (35.45%) spondyloarthritis and 15 (7.94%) undifferentiated inflammatory arthritis. The median duration of the disease course was 8 years [4-17], the mean age was 47.49 ± 13.70 years [14.74], 75.7% were women. The mean pain VAS was 4.77+-2.76 and 50.8% had a strong or moderate activity. The mean central sensitization score was 37.42+- 16.75, with 44.9% having a CSI score≥40.For treatments 38.2%of patients were on corticosteroids and 6.3%were using biological treatment. In uni and multivariate analysis,the parameters associated with CS were pain severity (0.039) and depression (≤0.001) A statistically significant correlation was found between the CSI-A score and pain VAS (r=0.32 p &lt;0.001) <h3>Conclusion</h3> Pain in patients with CIR has often been attributed to peripheral inflammation. However, our study suggests that central sensitization may increase pain intensity independent of disease activity. Screening for central sensitization mechanisms in patients followed for CIR seems necessary to guide management by targeting central pain in order to avoid useless therapeutic switches and escalations, sometimes even harmful for our patients. <h3>Reference</h3> [1]he International Association for the Study of Pain (IASP) 2014 https://www.iasp-pain.org/resources/terminology/ <h3>Acknowledgements:</h3> NIL. <h3>Disclosure of Interests</h3> None Declared.